I can confirm that (on my n900) 3rd party earbud/mic combos do not work. I experience the same symptoms as my purple friend (the OP). I would guess that this is because the n900 cannot tell the difference between a headphone/mic combo and a TV out jack by itself and some circutry in the nokia supplied accessories does this job. Then again I could just be talking out of my arse


This is what I am working with.